1. Tinkertoy is a trademark of Playskool, Inc., Pawtucket, RI 02862, and designates a children’s toy construction set consisting of straight wooden sticks and other simple elements insertable into spool-like connectors.
2. Michl, J., Kaszynski, P., Friedli, A.C., Murthy, G.S., Yang, H.-C., Robinson, R.E., McMurdie, N.D., and Kim, T. (1989) in A. de Meijere and S. Blechert (eds)Strain and Its Implications in Organic Chemistry, Kluwer Academic Publishers, Dordrecht, p. 463.
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